David decker



NITED STATES PATENT OFFICE.

DAVID DECKER, OF NEYV YORK, N. Y.

PIANOFORTE-ACTION.

Specification of Letters Patent No. 25,393, dated September 18, 1859.

To all whom Lt may concern.'

Be it known that I, DAvm Dncxnn, of New York, in the county and State of New York, have invented a new and useful Mode of Constructing Pianoforte-Actions; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawing, and to the letters of reference marked thereon, all of which form partof this specification.

The nature of my invention consists in an improved manner or mode of constructing piano-forte action known as a repeating action; by this construction a very desirable touch and quick motion of the action is obtained, and also, the different parts by which the action is regulated are placed convenient for adjustment.

To enable others, skilled in the art, to make and use my invention, I shall now describe its construction and operation.

The drawing represents a side view of the mechanism, (or action, as it is general termed) in elevation, the details of which I shall explain as I proceed.

The key (A) and the part (B) upon which the key rests and vibrates, and where it is held in its place by the keypin (C), have no particular features peculiar to themselves, and are well known and understood, therefore they need no further explanation here; to this key I attach an adjustable .piece (D), back of the keypin (C) by means 0f a screw (D1) passing through the adjustable piece D, at or near its center; the lower edge of this piece (D) toward the front of the key, is made beveling to nearly one half of its length, and is provided at or near its front end with a regulating screw (D2), by which the front end of the piece (D) may be either raised or lowered as circumstances may require. A repeating lever (E) is pivoted or hinged to the piece (D) at (El), it being about the center between the att-aching screw (D1) and the regulating screw (D2) g this repeating lever (E) is held up at the back end by a spring (E2), and at the front end is provided with a regulating screw (E3), by the use of which the repeating lever (E) is caused to assume a proper position. To the piece (D) is also pivoted or hinged a relieving jack (F) at (D3),near the center between the screw (D1) and the backend of the piece (D) this jack (E) has at the lower end, toward the front, a projecting arm (F1) which is connected with means of the screw (N).

a spring (F2) by the action of the spring (F2) against the arm (F15) this arm is broughtl or held up against a regulating screw (F3) which is attached to the repeating lever in front of the relieving jack (F). Attaching' this regulating screw (F3) to the key, or to any partwhich is carried by, and moves with the key, is peculiar to this mode of construction.

A hammerrail (G) is placed at a proper height above the center or nearly so, of the repeating lever to this hammerrail (G) is attached the hammer (H) by those parts connected directly with the hammer, these parts consist of the hammershank (I), the hammerbut (K) and the hammerflange (L), the hammerbut (K) is attached to the hammerflange (L) at the swinging center (M), and this hammerflange (L) is rmly fixed to the hammerrail (G) by To the hammerbut (K) is attached a lifting jack (O), pivoted, hinged or hung at (O1) the lower end of this lifting jack (O) has a transverse groove (O2), into this groove (O2) a tongue (O3) is made to t easily; said tongue is f fastened to the repeating lever (E) back of the relieving jack (F). Heretofore a pin and a hole have been used instead of this tongue and groove; but when a pin and a hole are used, the mechanism is liable to stick and become inactive in case any of these parts should become crooked; this sticking is prevented by using the groove instead of a hole, which allows playroom for any warping that may occur; instead of the tongue a pin may be used, but a tongue is better, as it will not indent the sides of the groove as a pin would do.

A spring (P) is attached to the repeating lever (E), this spring is made to extend under the lower end of the lifting jack (O) and assists in giving elasticity to the mechanism. The lifting jack (O) has a projection (1)) toward the front, just above the upper end (g) of the relieving jack (E). A regulating screw rail is placed back of the lifting jack (F) between the backend of the repeating lever and the hammershank (I) this rail is provided with a regulating screw (R) by which the upward motion of the backend of the repeating lever (E) is regulated; this rail (Q) serves also as a support for the hammer by having the hammershank rest upon this rail (Q), when the mechanism is in its normal posi- Cir tion. A backjack (S) is placed at or near the backend of the key (A) the duty of this backjack is to catch and hold the hammer (H) after it has given the blow, so as to prevent its rebounding.

Operation: After having all the different parts properly placed and adj usted, then, by depressing the key (A) in front of the. pin (C) the backend of the key (A) and those parts attached directly to the key are raised, and when the upperend of the relieving jack strikes under the projection (p) of the lifting ack (O) it causes the hammer (H) to iy up and give a blow; while the hammer is about giving the blow the backend of the repeating lever (E) comes in contact with the regula-ting screw which prevents the backend of the repeating lever from rising any higher, but as the key (A) with the piece (D) and relievingjack (F) are rising higher, the projecting arm (F1) of the relieving jack will come in contact with the regulating screw (F 3) which will depress the projecting arm (F1) and thus cause the upperend (g) of the relieving jack (F to be withdrawn from under the projection (79) of the lifting jack (O), this allows the hammer (H) to drop after it has given the blow, and is then caught as it descends, and held by the backjack (S), so as to prevent its rebounding; but when the backend of the key (A) is allowed to drop a little, then the hammer (H) will be relieved from the backjack (S), which will cause the hammer to rise slightly, and as the relievingjack (F) is lowered with the descent of the key (A), and the liftingjack (O) is held at a proper height by the repeating lever while the spring (E2) keeps the bac-kend of the repeating lever against the regulating screw (R) the upper end (g) of the relieving jack will slip under the projection (79) of the lifting jack (O), then the mechanism is ready for action again, and will act by but a slight motion of the key (A) this facilitates the repeating of the same tone, or sound, which can be performed with ease and in very rapid succession, which is a very important feature of a good piano forte.

`When it is necessary to remove the key (A) with its appendages, this can easily be effected by turning the hammer (H) upward and over toward the front, on the swinging center (DI) 5 the hammerbut by being turned over will raise the lifting jack (O) and thus disconnect it from the repeating' lever (E), then by raising the front end of the key (A) so that it will be withdrawn from the resting pin (C), the key may easily be removed. Formerly the regulating screw (F 3) used to be supported by the hammerrail (Gr), in which case it is greatly in the way of removing or replacing the key (A) this diliiculty is obviated by attaching the relieving ack regulating`- screw (F3) to the repeating lever or it might be attached to the key, or to some other part which is attached to and moves with the key, without altering the nature of my invention.

It is obvious that a great advantage is gained by placing the regulating screws (D2) and (E3) toward the front of the key, as they are thus conveniently located for regulating.

Having thus fully described my improved piano forte action, or mechanism, what I claim therein as new, and as my invention, and desire to secure by Letters Patent, is

l. I claim attaching the relieving-jacksregulating-screw (F3) directly to the key or to some part carried by the key, so that the repeating lever shall govern the action of the relieving jack by or through the said regulating screw; whether constructed in this precise manner, or in an equivalent, for the purpose as herein described.

2. I claim the groove in combination with the tongue, pin or equivalent, for the purpose of keeping the lifting ack in its proper position in relation to the repeating lever, and for preventing any binding o-r sticking of said repeating lever and lifting jack.

3. I claim so arranging the adjustable piece (D) and repeating lever (E) both, or either of them, so that their regulating screws (D2) and (E3) both, or either of them shall be at, or near the end next toward the front of the key, in front of the hammerrail, for the purpose of being thus conveniently placed for regulating.

DAVID DECKER.

W'itnesses:

F. O. DEGENER, JOHN J. DECKER. 

